1. Field of the Invention
The present invention relates to an automatic teller machine, and more particularly, to an automatic teller machine (hereinafter, referred to as xe2x80x9cATMxe2x80x9d) including a clutch device for selectively supplying power to a pick-up roller for extracting banknotes from a banknote storage cassette located within the ATM
2. Description of the Related Art
ATMs are convenient automated banking machines in widespread use which allow a user to easily withdraw or deposit money from or into his or her account anytime. An ATM is constructed such that a banknote storage cassette containing banknotes is installed at a certain location within the machine and a plurality of sets of driving rollers and driven rollers are driven to discharge banknotes stacked within the storage cassette to the outside
FIG. 1 is a schematic longitudinal sectional view illustrating a banknote discharging mechanism of a typical ATM. As shown in FIG. 1, the ATM includes a banknote storage cassette 12 detachably mounted to a frame 10 defining an internal space for stacking banknotes therein, a pick-up roller 14 for extracting individual banknotes from the banknote storage cassette located within the ATM, a plurality of sets of driving and driven rollers 18 and 16 for feeding banknotes extracted from the pick-up roller 14 to be discharged to the outside
The banknote storage cassette 12 is detachably mounted to the frame 10 and is managed such that it is always filled with banknotes. Also, the banknote storage cassette 12 is provided with a banknote extracting port for allowing a banknote to escape therefrom, and a pick-up roller 14 is disposed in front of the banknote extracting port. The pick-up roller 14, which forms a pair of rollers together with a driven roller 16, serves to extract banknotes one by one from the banknote storage cassette 12 and begin to feed the extracted banknotes.
The banknotes extracted by the pick-up roller 14 from the banknote storage cassette 12 are fed through a plurality of sets of driving and driven rollers 18 and 16 and are discharged one by one to the outside. A rotational driving force from a separate drive motor (not shown) is transmitted through a power transmission means such as gears, a belt or the like to a driving shaft for rotating each of the driving rollers 18.
In the meantime, the drive motor (not shown) rotates each of the driving rollers 18 and the pick-up rollers 16. At this time, a clutch device (not shown) is provided between the drive motor and the pick-up roller 14. The clutch device interrupts or permits transmission of a rotational driving force to the pick-up roller 14 from the drive motor so that a desired number of banknotes can be discharged to the outside. Accordingly, the pick-up roller 14 rotates only during the extraction of banknotes and waits in a stationary state where banknotes are not being extracted.
For example, in the case where five banknotes are withdrawn, the pick-up roller 14 extracts them from the banknote storage cassette 12 and then must stop its extracting operation. At this time, each of the driving rollers 18 continuously operates irrespective of the stopping of the extracting operation of the pick-up roller 14 and rotates until the fifth banknote extracted from the banknote storage cassette 12 is completely discharged to the outside of the ATM.
Accordingly, the rotational driving force transmitted to the pick-up roller 14 and the driving rollers 18 from the drive motor must be continuously transmitted to the driving rollers 18 during the discharge of the extracted banknotes, but must not be transmitted to the pick-up roller 14 immediately after the last one of the extracted banknotes is discharged to the outside. For the purpose of carefully controlling the rotational operation of the pick-up roller, a clutch device is installed between the drive motor (not shown) and the pick-up roller 14.
However, for a conventional clutch device employing a pair of oppositely faced friction plates, there has been a problem that if the friction plates are worn, performance and reliability of the clutch device are degraded. In addition, if the operation of the clutch device is interrupted in order to stop the pick-up roller 14 after discharge of the last banknote, the pick-up roller 14 is not stopped immediately by virtue of rotational inertia so that an extra banknote may be further extracted to some extent from the banknote storage cassette and then its extraction may be stopped. As a result, in the case where the next user withdraws banknotes from the ATM, the machine may malfunction and there may be a banknote jam due to the extraction of two or more overlapped banknotes between the pick-up roller and the driven roller, or the withdrawing operation may not be performed cleanly.
To solve the above-described problems, it is a primary object of the present invention to provide an automatic teller machine (ATM) including a clutch device in which the control performance of power transmission of the clutch device is no longer degraded even after use for an extended period of time by using gears, rather than friction plates in transmitting rotational driving force to a pickup roller, in which the pick-up roller can rapidly respond to the power transmission by the clutch device by employing an actuator for selectivity engaging or disengaging the gears, and which can prevent undesired extra rotation of a pick-up roller due to ordinary rotational inertia thereof by means of a stopping means for stopping the pick-up roller, to allow the pick-up roller to perform the correct extraction of banknotes.
In order to accomplish the primary object, according to an aspect of the present invention, there is provided an automatic teller machine (ATM) having a frame for defining an internal space, a banknote storage cassette installed within the frame for containing a plurality of banknotes, a pick-up roller for extracting the plurality of banknotes one by one, a plurality of driving rollers for feeding the banknotes extracted from the banknote storage cassette together with a plurality of driven rollers along a predetermined banknote traveling path to discharge them, the plurality of driving rollers each being rotated by means of a rotational driving force transmitted thereto from a drive motor, and a clutch device for selectively transmitting the rotational driving force generated from the drive motor to the pick-up roller, the clutch device including a driving gear rotatably mounted to the frame for receiving the rotational driving force from the drive motor to rotate the plurality of driving rollers, an idle gear engaged with the driving gear, a pick-up roller gear fixedly mounted on a rotating shaft of the pick-up roller and capable of being engaged with the idle gear for rotating the pick-up roller and, and a motor control means adapted to allow the idle gear to be engaged with or disengaged from the pick-up roller.
The motor control means may include an actuator laterally and fixedly mounted to the frame and having an actuator rod which operate in response to the external application of electric power thereto, and a support plate rotatably mounted to the frame such that a rotating shaft of the driving gear penetrates the support plate, the support plate supporting the idle gear and the driving gear such that they are engaged with each other and rotate about the rotating shaft of the driving gear in response to a longitudinal movement of the actuator rod so that the idle gear is engaged with or disengaged from the pick-up roller gear.
Also, the actuator and the support plate are coupled to each other by means of a link member such that the link member is coupled at one end to the actuator rod and at the other end to the upper end portion of the support plate with the other end of the link member having an extended slot formed therein, and a holding projection is formed at the upper end portion of the support plate so that it fits into the slot of the link member.
Preferably, the support plate includes a first elastic means for providing rotation momentum in a direction in which the idle gear is moved toward the pick-up roller, and a second elastic means for providing rotation momentum in a reverse direction to the direction of the first elastic means.
Further, the first elastic means is preferably a first tension coil spring disposed in parallel with the link member such that the first tension coil spring is coupled at one end to the actuator rod and at the other end to the support plate so as to provide a tensile force, and the second elastic means is preferably a second tension coil spring fixedly coupled at one end to the lower end of the frame and at the other end to the frame so as to provide a tensile force.
The support plate may include a stopping means for stopping the pick-up roller gear at the moment when the idle gear is moved away from the pick-up roller gear in response to the rotation of the support plate.
Also, the stopping means may include a latch gear fixedly mounted on the rotating shaft of the pick-up roller and having a plurality of V-shaped grooves, and a stopper fastened to the support plate, the stopper being moved into engagement with one of the plurality of V-shaped grooves to stop the pick-up roller gear at the moment when the idle gear is moved away from the pick-up roller gear in response to the rotation of the support plate.
The support plate is preferably composed of a rotatable support plate positioned between the frame and the driving gear, and a cover plate having the same shape as the rotatable support plate and rotatably mounted on the rotating shaft of the driving gear in parallel with the rotatable support plate such that the driving gear and the idle gear are engaged with each other between the rotatable support plate and the cover plate.